(Yicai Global) July 4 -- Chinese drugmaker Sino Biopharmaceutical has started the third and final stage of clinical trials for its norovirus vaccine and is on track to produce the world’s first jab for the common stomach bug.

The vaccine, jointly developed by Sino Biopharma and the Lanzhou Institute of Biological Products, has already been administered to its first human subjects, Beijing-based Sino Biopharma said on its social media account yesterday.

The norovirus jab was the first in the world to be approved for clinical trials when Chinese authorities gave it the greenlight in 2019, Sino Biopharma said. Results from the first and second phases have shown the vaccine to be stable and to confer strong immunity, it added.

At present there are no specific vaccines or drugs available on the market for the norovirus, whose symptoms include nausea, vomiting and stomach ache. Treatment mostly targets symptoms and offers supportive therapies. Outbreaks normally occur in confined environments such as schools.

The norovirus is an RNA virus and prone to mutations, so new variants will emerge every few years, a source from a vaccine company told Yicai Global. Most infections are not reported because the majority of healthy adults with high immunity recover within a few days, which makes it difficult to predict the next outbreak.

The culture conditions are extremely complicated and culture costs are expensive as commonly used cell strains cannot be infected with the norovirus, and the amplification of progeny norovirus can only be detected on B-type white blood cells and intestinal organoid cells, the person said.

Other Chinese vaccine makers, such as Chongqing Zhifei Biological Products and Chengdu Kanghua Biological Products, are also taking part in the race to produce a norovirus vaccine. Zhifei’s quadrivalent recombinant norovirus vaccine is in the second stage of clinical trials, the firm said in its 2022 annual report.

Editor: Kim Taylor